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The official control of animal proteins in feed is focused on the prevention of Bovine Spongiform Encephalopathy (mad cow disease). The current legislation of the European Union is planned to avoid the feeding of animal by-products to the same species as its origin (ban of cannibalism, or species-to-species ban). With respect to the official control, the circumscription of the term species in legislation should be defined, and species-specific markers should be available. Markers will include primer sets, antibodies, near-infrared profiles or visual characteristics. The method of classical light microscopy is currently the only accepted method in the framework of the official detection of animal proteins. Besides the necessary development of complementary methods, either as stand alone methods or in combination, the visual characteristics used for a microscopic examination of meat and bone meal particles should be fully explored. Multivariate analysis of a range of characteristics of lacunae in bone fragments revealed that discrimination is possible between mammalian and avian bone fragments. Translation to features for every day practical use should be carried out very carefully, and only comprehensively collected information on a range of features will give a first indication of the source. Characteristics of hairs and feather filaments can be used to identify the origin of animal particles. An in situ identification method has been developed for antibody conjugation with troponin I in muscle fibers on a microscopic slide. A proof of principle is presented. Interlaboratory transferability and validation have still to be achieved. The development and testing of light microscopy markers in the framework of the SAFEED-PAP project revealed that a fine tuning of existing microscopic characteristics appears to be possible.

A plasmid, pWEH1, was constructed containing a fusion of the DNA encoding the signal sequence of the Escherichia coli outer-membrane protein A to the 5′-end of a glyceraldehyde-3-phosphate dehydrogenase cDNA from Ricinus communis. When expressed in E. coli, the fusion protein was secreted by the normal membrane-potential-dependent pathway. Processing by signal peptidase was inhibited by low concentrations of phenethyl alcohol. Quantitative cell fractionation was used to show that the mature plant protein was associated with the bacterial outer membrane. The protein could not be released from the membrane by washing with alkaline sodium carbonate. Radioactivity from [U-14C]-palmitate was incorporated into the heterologous protein. These results suggest that the sequence of this normally cytoplasmic enzyme contains a cryptic lipid-modification site, and the combination of a signal sequence plus a lipid-modification sequence results in specific targeting to the bacterial outer membrane. [ABSTRACT FROM AUTHOR]

Of 142 adult patients undergoing open-heart surgery, 123 were extubated either in the operating room or within 3 hours after admission to the recovery room, to avoid the discomfort and risks of prolonged mechanical ventilation. The remaining 19 patients, who had impaired cardiac function, were mechanically ventilated for 1 to 7 days postoperatively. The most important criteria for cardiopulmonary malfunction indicating the need for continued mechnical ventilation were a low mixed venous O2 saturation (SVO2) of less than 60% and a high left atrial pressure (greater than 20 torr). Of the 123 patients, 118, had an uneventful postoperative recovery and 5 needed reintubation, 2 because of low SVO2 and 3 because of complications unrelated to respiratory management. Most adult patients can spontaneously breathe adequately immediately after or within 3 hours of completed open-heart surgery, but a thorough physiologic and clinical evaluation should precede extubation, to identify those who need prolonged mechanical ventilation in the postoperative phase. Criteria for selection of patients for early extubation are presented.